Answered by: James L. Cook, DVM, PhD, DACVS, DACVSMR:
It is hard to accurately answer this question because of all the variables involved. Certainly progress has been made in decreasing the incidence of hip dysplasia and elbow dysplasia through registries (OFA) and responsible breeding. Cranial cruciate ligament disease is increasing in numbers, but it is hard to know if that is because clients are seeking healthcare more for their dogs, we are doing a better job diagnosing it, or it is directly or indirectly related to breeding. Of course, I do very strongly support responsible breeding based on data from registries and pedigree depth.
